"May I be excused? My brain is full"

Looking round the roomful of 500+ consultants on Thursday night reminded me of a phenomenon that, for me, kicked in some years ago. I started seeing people who reminded me of other people. The doppelganger count suddenly went into the red zone. It was like I had seen so many faces that I had seen them all and was starting to see repeats. In truth of course they are all unique, it must be the granularity of my perception that is the limiting factor.